Houghton Mifflin Harcourt
Holt, Rinehart and Winston: Homework Help Independent Practice: Other Sequences
Get independent practice working with scientifc and standard notation. Each incorrect response gets a text box explanation and another try. Correct responses are confirmed.
Wolfram Research
Wolfram Math World: Sequences
This MathWorld page provides links to various specific types of mathematical sequences and related links. This is a great resource if you are looking for very specific information.